CAS-SC: Understanding Synergistic Effects of Organic Mixtures for Electrocatalytic Hydrogenation for Fuel Production

This project aims to advance knowledge of electrocatalytic hydrogenation (ECH) of bio-oil. Waste biomass (e.g., biomass sources separate from those that are used for food) can be heated at high temperatures to form bio-oil, which contains many of the important compounds for fuels, but with low energy density. Using renewable electricity, ECH of this bio-oil can form chemicals that have higher energy density and can be used as fuels. Thus, this project will study a method to provide high energy density transportation fuels with net-zero carbon dioxide emissions as an alternative to petroleum. The goal of this project is to fundamentally understand how to simultaneously upgrade multiple organic molecules relevant to bio-oil mixtures via electrocatalysis. Particularly, the team will investigate conditions where the different organic molecules can help one another in converting to the desired products. This research would enable sustainable bio-based products, use renewable energy more efficiently to drive chemical processes, help develop carbon-neutral processes for fuel production, and use predictive modeling to understand electrocatalytic reactions. The proposed education and outreach activities will engage underrepresented high-school students in research and help 4th and 5th grade students understand more about chemistry and why it is important and interesting, helping to foster the next generation of STEM professionals. The project goal is to understand the ECH of model bio-derived organic mixtures to determine how multiple organic molecules can be simultaneously electrochemically upgraded with high efficiency. This joint experimental and computational project will investigate ECH of organic molecules (i.e., mixtures of phenolics and terpenes) that are present in biomass-based feedstocks and investigate how the reaction of these molecules in mixtures differs from that of each molecule individually. This project will identify organic molecules that synergistically enhance one another’s conversion and understand the origin of this synergistic enhancement on metal and alloy electrocatalysts, such that electrochemical reactor design can be used to decrease the cost of fuels produced by ECH of bio-derived organics. The three major tasks of this work are to: (1) Understand ECH of model organic molecules in isolation; (2) Elucidate how model organic mixtures enhance or slow ECH; and (3) Design systems for simultaneous hydrogenation of organic mixtures. This research will elucidate reaction mechanisms for ECH of bio-oil mixtures and generate knowledge about the role of the applied electrochemical potential and water solvent for ECH using quantum mechanical modeling and experimental kinetics measurements and spectroscopy. Also, this work will clarify the role of co-adsorbed organics on the rate and selectivity of electrocatalytic hydrogenation and identify rates of electrochemical conversion to evaluate commercial feasibility compared to the state-of-the-art. This research will generate fundamental knowledge that can be used to enhance the efficiencies for bio-based fuel manufacturing processes at scale using renewable energy. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.